Joyner played football for Penn State in the 1970s. He wrestled for Penn State as well, finishing second in the 1971 NCAA Championships at heavyweight. He graduated from Penn State in 1972 with a degree in science, and received his medical doctorate from Penn State in 1976. He worked as an orthopedic surgeon, and later worked with the World Football League. He focused his career on sports medicine, eventually serving as chair of the United States Olympic Sports Medicine Committee.